JP2000205968A - Measuring probe and measuring apparatus and facility with at least one measuring probe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical-fiber probe which can be installed easily and a measuring apparatus and facility having the probe. SOLUTION: This probe includes at least one optical fiber cable 13, 20 and an electric circuit 12 having retaining members 14 optically connected to signal conversion means 4, 21 for retaining optical-fiber elements. The electric circuit has a removable electric connector 15 connected to the signal conversion means such as light emitting diodes and/ or photodetectors and supplies or receives electric signals 17, 22 for use by a processing circuit 6. This measuring apparatus has at least one optical-fiber probe connected to the processing circuit 6 by the removable electric connector 15. Particularly applied to a temperature measuring probe and apparatus having optical fibers and a facility having conductors.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring probe having at least one fiber optic cable, an apparatus comprising the measuring probe and signal processing means, and at least one conductor and a facility comprising the measuring probe.

[0002]

2. Description of the Related Art Known fiber optic measurement probes generally include at least one optical fiber, a first end of which is connected to a sensor and a second end of which is connected to a sensor.
Is connected to an electrical processing unit. To connect such an optical fiber to the processing apparatus, it is known to use a removable optical connector designed to cooperate with an optical or opto-electrical element fixedly connected to the processing apparatus. Have been.

[0003]

In order to couple the optical signal flowing through the fiber so that the intensity of the optical signal is maximized, it is necessary to precisely align the optical connector with another fiber or opto-electrical element. is necessary. In addition, optical connectors are expensive and bulky, which makes it difficult to share them with equipment that requires several measurement points. Particularly when using an optical fiber probe in an industrial environment, the optical connector is susceptible to stress, and this stress can damage the optical connection when adapting or handling the optical connection.

[0004] Adapting or replacing probes in industrial equipment must be done by employees who know the equipment. Employees are not always good at connecting fiber optics and do not always have the tools to accomplish this at the facility site. Thus, known fiber optic probes have not always been easy to use without resorting to special technical measures in industrial equipment and without strictly combining precautionary measures within the premises of such equipment.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to achieve an optical fiber probe which can be easily installed, and a measuring apparatus and equipment provided with the probe.

[0006]

An optical fiber measuring probe according to the present invention comprises at least one optical fiber cable, at least one electric circuit having first electric connection means, and one end of the optical fiber cable. At least one temperature sensor provided, and connected to the first connection means, so that an optical signal propagated by the optical fiber cable disposed together with the temperature sensor and flows through the first connection means. Signal conversion means designed to provide an interface with the designed electrical signal, and at least one optical fiber strand arranged with the temperature sensor and optically connected to the signal conversion means Optical fiber holding means for holding the optical fiber.

[0007] In a preferred embodiment of the present invention, the probe includes an amplifying means connected between the signal conversion means and the first connection means.

[0008] The probe includes a sensor provided on the optical fiber cable and responsive to an optical signal generated from the temperature sensor and representing a physical quantity to be measured.

Advantageously, the probe comprises a storage means for storing correction parameters or setting parameters.

[0010] It is preferable that the signal conversion means includes at least one photodetector for converting an optical signal supplied to one end of the optical fiber into an electric signal.

The signal conversion means includes at least one light transmission means for converting an electric signal generated from the first electric connection means into an optical signal and inputting the converted signal to one end of the optical fiber. It is preferable that the optical fiber maintain the optical connection with the light transmitting means.

In a specific embodiment of the present invention, the probe includes a temperature sensor provided at one end of the optical fiber cable, and a light emitting element. Exciting the element, a second optical signal is transmitted from the light emitting element and propagated to the signal conversion means via the optical fiber cable, and the second optical signal is different from the wavelength of the first optical signal It has a wavelength and an attenuation that represents temperature.

The probe includes first and second optical fiber wires disposed between the temperature sensor and the signal conversion means, wherein the first optical fiber wire is the first optical fiber wire.
It is preferable that the second optical fiber conducts the second optical signal.

For example, the probe may include a light separating system disposed between the optical fiber and the signal conversion means.

In order to filter an optical signal, the probe may include an optical filter disposed between one end of the optical fiber and the signal conversion means.

Preferably, the optical fiber cable has an optical fiber wire formed of a plastic material.

It is advantageous that the optical fiber holding means includes a positioning portion for determining a position of the optical fiber on the signal conversion means.

Preferably, the optical fiber holding means includes a guide member.

According to a preferred embodiment of the present invention, the signal conversion means holds at least one light emitting diode, a photodetector, and an optical connection with the light emitting diode while holding a first optical fiber. And fixing means for holding the second optical fiber and fixing the optical connection with the photodetector.

In order to focus the three measurement channels, the probe holds the three first optical fiber wires, fixes the optical connection with the three light emitting diodes, and fixes the three second optical fibers. And fixing means for fixing the optical connection with the three photodetectors while holding the optical fiber.

In order to reduce the volume of the probe, the light emitting diode and the first connection means are arranged on a first printed circuit, and the photodetector is arranged on a second printed circuit, The second printed circuit is the first printed circuit.
Are electrically connected to the printed circuit and are arranged substantially orthogonally.

To protect electrical or opto-electrical components, the probe comprises an insulating first coating over at least a portion of the electrical circuit, and the insulating first coating.
And a conductive second coating that covers at least a portion of the coating.

In a preferred application, the probe is used to measure the temperature of at least one electrical conductor.

A measuring apparatus according to the present invention having an optical fiber cable comprises a signal processing means, the above-described probe,
Second connection means connected to the signal processing means and designed to cooperate with the first connection means.

[0025] The installation according to the invention comprises at least one electrical conductor and at least one said probe connected to this electrical conductor.

[0026]

BRIEF DESCRIPTION OF THE DRAWINGS In the following, other advantages and features of the present invention will become more apparent according to the description of some embodiments of the present invention shown in the accompanying drawings. However, it goes without saying that these embodiments do not limit the present invention.

In the known embodiment shown in FIG. 1, the optical fiber sensor 1 has an optical fiber cable 2 connected to an optical connector 3. These optical connectors are detachable and cooperate with the optoelectronic devices 4 and 5 connected to the processing circuit 6 of the centralized measuring device 8. The optoelectronic device may in particular comprise a photodetector 4 for receiving an optical signal or a light emitting diode 5 for emitting an optical signal. It is preferable that an amplifier 7 for amplifying an electric signal representing an optical signal is connected between the photodetector 4 and the processing circuit 6.

In certain cases, an intermediate fiber can be used between the optical connector and the optoelectronic device.

When the sensor is used in an industrial facility having the measuring device 8, optical connection with the connector 3 may not be completely achieved. In reality, special tools are sometimes needed and adjusting the optical engagement between the optical connector 3 and the optoelectronic devices 4 and 5 requires a competent employee. In addition, if the optical connection is not good, the loss of light is too great and the measurement by the sensor tends to be erroneous.

Other disadvantages of using optical fiber cables with optical connectors include the potential for degradation of the optical connector. The sensor is exposed to virtually any type of mechanical compression or atmospheric pressure, which can change the characteristics of the optical connection. For example, the optical connector may be dirty, a part of the optical connector may be blocked, or may be wrapped in moisture or dust.

In one embodiment of the sensor according to the present invention, the sensor comprises an electrical circuit, and an optical fiber cable establishes an optical connection between the signal converting opto-electrical device connected to the electrical connector on the electrical circuit. Is held. in this case,
The end user receives the sensor with the optical connection already installed. This allows the user to connect the sensors electrically without having to bother with the optics, especially if he is a specialist in electrical installations. Since the optical connection is achieved in an optimal manner and is hermetically protected, no external compression has any effect and the measurement by the sensor is not adversely affected.

FIG. 2 shows a measuring apparatus provided with two optical fiber sensors 10 and 11 according to the first embodiment of the present invention. The first sensor 10 includes an electric circuit 12 such as a printed circuit, on which an optical detector 4 is optically connected to an optical fiber 13 held and protected by a holding member 14. I have. The electric circuit 12
It has a detachable electrical connector 15 designed to cooperate with an electrical connector 16 secured to the measuring device 8. The electric circuit 12 can also include an amplifier 7 connected between the light detector 4 and the electric connector 16. In the present embodiment, the electrical connectors 15 and 16
Also, the electrical measurement signal 17, the reference line 19 and the power line 18
And lead.

The second sensor 11 is provided with an electric circuit 12 such as a printed circuit or a hardwired circuit.
Are optically connected to the light emitting diode 21, which is held and protected by the holding member 14. The light emitting diode 21 is connected to a detachable electric connector 15 provided on the electric circuit 12, and the electric connector 15 is designed to cooperate with an electric connector 16 fixed to the measuring device 8. . In FIG. 2, the electrical connectors 15 and 16 have a connection point for sending the electric signal 22 to the light emitting diode 21 and a connection point with the reference line 19. The signal 22 supplied from the processing circuit 6 is
The signal can be amplified by the amplifier circuit 23.

In a preferred embodiment of the present invention, all the connection points of the electrical connector 15 can be combined on a single electrical connector, and the optical fiber strands 13 and 20 can be combined.
Can be associated with a single measurement and can be maintained on a single electrical circuit 12.

FIG. 3 shows a circuit diagram of a measuring device and a sensor 24 provided with two optical fiber wires 13 and 20 connected to a sensor 25. One end of each of the two optical fiber wires is held on the electric circuit 12 and optically connected to the signal conversion devices 4 and 21, and the other end of each fiber wire is connected to the sensor 25.

The first fiber strand 20 is connected to the electric circuit 12
One end is optically connected to the light emitting diode 21 and the other end is connected to the sensor 25. The second optical fiber 13 is held toward the electric circuit 12,
One end is optically connected to the photodetector 4 and the other end is also connected to the sensor 25.
It is connected to the. 3, the photodetector 4 is a phototransistor connected to the input of the amplifier 7, and the output of the amplifier 7 is connected to a detachable electrical connector 15. The light emitting diode 21 is connected to the electric connector 15 via the amplifier circuit 23. Electrical connector 15
Can be connected to the fixed electrical connector 16 of the measuring device 8.

The processing circuit 6 is connected to the fixed electrical connector 16. The processing circuit 6 sends a control signal 22 to the diode 21, and alternately receives a measurement signal 17 from the photodetector 4. The control signal 22 is converted by the light emitting diode 21 into a first optical signal 26,
Flows through the first optical fiber 20 to excite the sensor 25. Next, the second optical signal 27 emitted from the sensor 25 flows in the second optical fiber 13 and flows through the photodetector 4.
, And the photodetector 4 converts the second optical signal 27 into an electric signal 17. This signal is amplified by the amplifier 7 and supplied to the processing circuit 6 via the electrical connectors 15 and 16.

The measurement by the sensor is reliable and reliable, since the optical connection is adjusted in an optimal way, thereby holding the fiber fixed. Furthermore, the sensor is provided by a simple electrical connection of the detachable electrical connector 15.
It can be easily installed and easily replaced.

In order to improve the interchangeability of the sensor, a set parameter or a correction parameter can be stored in a storage circuit 28 provided in the electric circuit 12. Thereby, the probe provided with the sensor 25 can be adjusted at a factory or a special place in assembly. Thereby, it can be used easily without adjustment in industrial equipment. The setting or correction parameters may relate in particular to a continuous offset or amplitude or distortion response, decay over time, lag time or response table. When the probe is connected to the processing circuit 6, information 32 representing a setting parameter is supplied to the processing circuit 6. In this way, since each probe comprises a storage circuit, the processing circuit 6 can modify and adapt the electrical signal flowing through the fiber and representing the optical signal representing the physical measurement. This information 32 is propagated via electrical connectors 15 and 16.

FIG. 4 shows the first and second optical signals 26, 2
FIG. 2 shows a circuit diagram of a measuring device and a probe provided with an optical fiber wire 29 through which a wire 7 flows. The optical fiber wire 29 has one end connected to the sensor 25 and the other end connected to the light emitting diode 21.
And the holding member 14 which is optically connected to the photodetector 4 so as to face the electric circuit 12. Separating element 30 having a semi-reflective plate is connected to one end of fiber strand 29 and diode 21
And a photodetector 4 for separating a signal 27 coming from the fiber and the sensor to the photodetector 4 and a light signal 26 from the diode to the fiber and the sensor. In other embodiments, the separation element can be a fiber optic power splitter.

If the signals 27 and 26 have different wavelengths, an optical filter 31 is placed immediately before the photodetector 4 to improve the separation quality. Due to the presence of the optical filter 31, the signal 27 having the first wavelength can pass and the signal 26 having the second wavelength cannot pass. In this probe, the electrical circuit 12 comprises a power supply line 18, a reference line 19, a measurement signal 17 and a detachable electrical connector 15 for conducting a control signal for the diode 21.
Is provided.

FIG. 5 shows a sensor that can be used for the probe according to the present invention. This sensor provides a first signal 2
6 is provided with a member 33 that receives and responds to this. Next or simultaneously, the second optical signal 27 is transmitted by the member 33. This second optical signal 27 indicates a physical quantity to be measured. Note that in certain embodiments this physical quantity is temperature.

When the member 33 is a fluorescent member or a light emitting member, the second signal 27 has a wavelength different from the wavelength of the first signal 26. In addition, when the first signal 26 stops illuminating the member 33, the light intensity of the second signal 27 decays almost exponentially over time. In particular, when the member 33 is a ruby or powdered alexandrite, the attenuation 34 of the second signal 27 indicates the temperature of the member 33.

FIG. 6A shows the optical amplitude of the first signal 26 irradiating the member 33, and FIG.
2 shows a second signal 27 emitted by. Processing circuit 6
Is the attenuation 3 of the second signal 27 which is converted to an electrical signal 17
According to 4, the value of the temperature in the member 33 is determined.

FIG. 7 shows a circuit diagram of an optical fiber probe for three measurement channels. First optical fiber 20
a, 20b, 20c, the sensor 2
5a, 25b, 25c are connected to light emitting diodes 21a, 21
b, 21c and the second optical fiber 1
3a, 13b, 13c are sensors 25a, 25b, 25
c is connected to a photodetector indicated by photodiodes 4a, 4b, 4c.

The six optical fibers 20a, 20b, 2
Oc, 13a, 13b and 13c are held by the holding member 14 so as to be directed to the electric circuit 12. The three light emitting diodes 21a, 21b, 21c are connected to the detachable electrical connector 15 to control signals 22a, 22b.
And 22c, respectively. The photodiodes 4a, 4b, 4c optically connected to the second optical fiber strands 13a, 13b, 13c respectively include amplifiers 7a, 7b, 7c.
c.

The amplification degree of each amplifier is determined by each of the amplifiers 7a and 7a.
It is determined by the resistors 36a, 36b and 36c connected between the output and the inverting input of b and 7c respectively. The output of the amplifier is connected to the
It supplies measurement signals 17a, 17b, 17c respectively representing the measurements by 5a, 25b, 25c. Electrical connector 1
5 also supplies a reference line 19 and two power lines V + and V- to supply power to the amplifier.

In the embodiment shown in FIG. 7, the sensors 25a, 25b, and 25c are temperature sensors provided with a fluorescent material or a luminescent material that operates, for example, like the sensor shown in FIG. The probe shown in FIG. 7 has conductors 37a, 37b,
Useful for temperature measurement of electrical equipment with 37c. Due to the high dielectric strength of the optical fiber, the probe shown in FIG. 7 can be used in equipment with high voltages, especially low, medium or high voltages.

FIG. 8 shows a portion of the three channel probe shown in FIG. In the present embodiment, the electric circuit 12
Has two printed circuits 38 and 39 arranged substantially orthogonally. First printed circuit 38
Comprises the light emitting diodes 21a, 21b, 21c and the electrical connector 15, and the second printed circuit 39 comprises:
In addition to the amplifiers 7a, 7b, 7c, the photodetectors 4a, 4b,
4c. These two printed circuits are mechanically and electrically connected. With such an arrangement,
The volume of the probe is sufficiently reduced, and the connection area with the measuring device is also sufficiently reduced.

FIG. 9 shows a side view of the probe shown in FIG. In this embodiment, the first optical fiber 20
a, 20b, 20c are light emitting diodes 21a, 21b,
It is placed in an orifice provided in 21c. FIG. 9 shows the fiber 20a inserted in the light emitting diode 21a. Second optical fiber strands 13a, 13b, 13c
Are mounted so as to be optically connected to the photodetectors 4a, 4b, 4c, respectively. Thus, the optical fiber 13a
Is placed so as to face the photodetector 4a. To improve operation, pass the signal emitted by the sensor,
To stop the signal generated by the light emitting diode,
An optical filter 31 provided between the second optical fiber 13a and the photodetector 4a filters the optical signal.

In the embodiment shown in FIG. 9, the optical fiber holding member 14 includes a member 40 for fixing and positioning the optical fiber. The optical fiber can be packed in the member 40 by charging the material 41 into the concave portion 42 of the member 40 that receives the optical fiber.

In the embodiment shown in FIG. 10, the holding member 14 has a base 43 and an optical fiber guide member 45.

According to a different embodiment, the probe comprises an insulating first coating 47 over the electrical components of the electrical circuit 12 and a conductive second coating 48 over the insulating first coating. It is preferable to provide.
This conductive second coating has the function of an electromagnetic shield. The materials that make up these coatings are:
Preferably it is a polymer.

In order to fix the optical fiber probe to the measuring device 8, the electric circuit 12 or the electric connector 15 includes a holding member 46 for fixing the detachable electric connector 15 to the fixed electric connector 16.

In another embodiment, the electrical circuit 12 comprises
It can be a metal wiring circuit, an impregnated circuit, or a circuit suitable for, for example, a surface mount component.

[0056]

As described in detail above, according to the present invention,
Provided are an optical fiber probe that can be easily installed, and a measuring device and equipment provided with the optical fiber probe.

[Brief description of the drawings]

FIG. 1 is a wiring diagram of a known type of optical fiber probe.

FIG. 2 is a first circuit diagram showing a first embodiment of the optical fiber probe according to the present invention and a first embodiment of the device according to the present invention.

FIG. 3 is a second circuit diagram showing a second embodiment of the optical fiber probe according to the present invention and a second embodiment of the device according to the present invention.

FIG. 4 is a third circuit diagram showing a third embodiment of the optical fiber probe according to the present invention and a third embodiment of the device according to the present invention.

FIG. 5 shows a sensor that can be connected to an embodiment of the probe according to the invention.

FIG. 6 shows signals that can flow in an optical fiber included in an embodiment of the probe according to the present invention.

FIG. 7 is a circuit diagram showing an embodiment of a probe according to the present invention having three measurement channels.

8 is a circuit diagram of a probe having three measurement channels according to the circuit diagram shown in FIG. 7;

FIG. 9 is a side view of a probe according to an embodiment of the present invention.

FIG. 10 is a perspective view of a probe with improved support means with the probe shown in FIG. 7;

[Explanation of symbols]

2 Optical fiber cable 4, 4a-c Photodetector 6 Signal processing circuit 7a-7c Amplifier 8 Measuring device 10, 11 Optical fiber sensor 12 Electric circuit 13, 13a-c, 20, 20a-c, 29 Optical fiber strand 14 , 40-45 Optical fiber holding member 15, 16 Electric connector 17, 22 Electric signal 21, 21a-c Light emitting diode 25, 25a-c Sensor 26, 27 Optical signal 28 Storage means 30 Optical separation system 31 Optical filter 33 Light emitting element 37a -C conductor 38,39 printed circuit 45 guide member 46 support member 47 insulating first coating 48 conductive second coating

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Bansin, Miniet Meran, France, Ryu, Shan, Rocha, France 28 (72) Inventor Jean-Louis, Robato Melan, Shmann, de, La, Tire, France 38 (72) Inventor Christian, Petit Biff, Ale, Ple, Giraud, France 11 (72) Inventor Pierre, Ambral France, Meran, Alley, de la La Rosliere, 8 (72) Inventor Alain, Elmir -Baudin France, Saint-Tismier, Le, Cle, Do, Syorm, 129 F-term (reference) 2F056 GA06 2F073 AA22 AB06 AB12 BB06 BC04 CC01 FF08 FF14 GG03

Claims (20)

[Claims] At least one fiber optic cable,
An optical fiber measurement probe comprising: at least one electric circuit having a first electric connection means, wherein at least one temperature sensor provided at one end of the optical fiber cable is connected to the first connection means. And designed to provide an interface between an optical signal propagated by the fiber optic cable disposed with the temperature sensor and an electrical signal designed to flow in the first connection means. And a signal conversion means provided with the temperature sensor, and an optical fiber holding means for holding at least one optical fiber that is optically connected to the signal conversion means. . 2. The probe according to claim 1, further comprising an amplification unit connected between said signal conversion unit and said first connection unit. 3. The probe according to claim 1, further comprising a sensor provided on the optical fiber cable and responsive to an optical signal generated from the temperature sensor and representing a physical quantity to be measured. 4. The probe according to claim 1, further comprising storage means for storing a correction parameter or a setting parameter. 5. The apparatus according to claim 1, wherein said signal conversion means includes at least one photodetector for converting an optical signal supplied to one end of said optical fiber into an electric signal.
5. The probe according to any one of items 4 to 4. 6. The signal conversion means includes at least one light transmission means for converting an electric signal generated from the first electric connection means into an optical signal and inputting the converted signal to one end of the optical fiber. The probe according to any one of claims 1 to 5, wherein the optical fiber is maintained in an optical connection with the light transmitting means. 7. The temperature sensor provided at one end of the optical fiber cable includes a light emitting element, and a first optical signal is sent from the signal conversion means to excite the light emitting element, and a second light is emitted. A signal is sent from the light emitting element and propagated to the signal conversion means via the optical fiber cable, and the second optical signal has a wavelength different from the wavelength of the first optical signal and an attenuation representing temperature. The probe according to any one of claims 1 to 6, wherein the probe has: 8. A method according to claim 1, further comprising a first optical fiber and a second optical fiber disposed between the temperature sensor and the signal conversion means, wherein the first optical fiber is a first optical signal. The probe according to claim 7, wherein the second optical fiber conducts the second optical signal. 9. The probe according to claim 1, further comprising a light separation system disposed between the optical fiber and the signal conversion means. 10. The probe according to claim 1, further comprising an optical filter disposed between one end of the optical fiber and the signal conversion means. 11. The probe according to claim 1, wherein the optical fiber cable has an optical fiber wire formed of a plastic material. 12. The probe according to claim 1, wherein said optical fiber holding means includes a positioning portion for determining a position of said optical fiber on said signal conversion means. 13. The probe according to claim 1, wherein said optical fiber holding means includes a guide member. 14. The signal conversion means includes: at least one light emitting diode; a photodetector; the first optical fiber optically connected to the light emitting diode; 14. The probe according to claim 1, further comprising: fixing means for holding the second optical fiber connected to the probe. 15. The three first optical fiber wires optically connected to the three light emitting diodes, and the three second optical fibers optically connected to the three light detectors. The probe according to claim 13, further comprising fixing means for holding the optical fiber. 16. The light emitting diode and the first connection means are provided on a first printed circuit, the photodetector is provided on a second printed circuit, and the second printed circuit is provided on a first printed circuit. , Electrically connected to the first printed circuit,
2. The device according to claim 1, wherein the components are arranged so as to be substantially orthogonal.
16. The probe according to any of 4 or 15. 17. A semiconductor device comprising: an insulating first coating covering at least a part of the electric circuit; and a conductive second coating covering at least a part of the insulating first coating. Claims 1 to 16
The probe according to any one of the above. 18. The probe according to claim 1, which is used for measuring a temperature of at least one electric conductor. 19. A signal processing means, wherein at least one of the probes according to claim 1 is connected to said signal processing means, and is designed to cooperate with said first connection means. An optical fiber measuring device, comprising: a second connecting means. 20. An installation comprising at least one electrical conductor and at least one of the probes according to claim 1 connected to said electrical conductor.